Trapezoid mesa trench metal-oxide semiconductor barrier Schottky rectifier: an improved Schottky rectifier with better reverse characteristics

Abstract

An improved structure of Schottky rectifier, called a trapezoid mesa trench metal-oxide semiconductor (MOS) barrier Schottky rectifier (TM-TMBS), is proposed and studied by two-dimensional numerical simulations. Both forward and especially better reverse I—V characteristics, including lower leakage current and higher breakdown voltage, are demonstrated by comparing our proposed TM-TMBS with a regular trench MOS barrier Schottky rectifier (TMBS) as well as a conventional planar Schottky barrier diode rectifier. Optimized device parameters corresponding to the requirement for high breakdown voltage are given. With optimized parameters, TM-TMBS attains a breakdown voltage of 186 V, which is 6.3% larger than that of the optimized TMBS, and a leakage current of 4.3×10−6 A/cm2, which is 26% smaller than that of the optimized TMBS. The relationship between optimized breakdown voltage and some device parameters is studied. Explanations and design rules are given according to this relationship.